“Shortcuts” are a special set of REPL commands that are invoked by name. To invoke a shortcut you first press , (comma) at the REPL prompt and then enter the shortcut's name when prompted.
Shortcuts deal with things like switching between directories and
compiling and loading Lisp systems. The exact set of shortcuts is not
currently documented in this manual, but you can use the help
shortcut to list them interactively.